Mothers of very low birthweight infants (VLBW; equal to or less than 1500 grams) experience higher anxiety and depression the week of the infant's birth and the week prior to the infant's hospital discharge, than do mothers of normal weight infants. In caretakers of the elderly a relationship has been established between increased anxiety and depression, impaired immune function, and poorer health. If this relationship exists in mothers of VLBW infants nursing interventions to decrease anxiety and depression or to lessen their impact could be designed and tested. These interventions may include efforts to decrease maternal exposure to infection, or improve other circumstances that may potentiate impaired immune function such as fatigue. Similarly interventions that lessen the impact of increased anxiety and depression on maternal infant interactions or on maternal and infant health could be designed and tested. These interventions may include relaxation and coping techniques that have been demonstrated to improve immunologic function. The purpose of this study is to examine changes in anxiety and depression and immune function in mothers of VLBW infants and to compare these responses to those of mothers of healthy term (greater than 37 weeks gestation) infants. Specifically changes in anxiety, depression, and in immune function will be examined in 64 mothers of VLBW infants and a comparison group of 64 mothers of healthy normal weight (birthweight greater than 2500 grams) infants at delivery, 1, 2, and 4 months postpartum and the week before VLBW infant hospital discharge. Anxiety and depression will be measured using two questionnaires: Multiple Affect Adjective Checklist-Revised and the Symptom Checklist 90-Revised and a structured interview. Changes in immune function will be measured by examining alterations in circulating lymphocyte subsets and disturbances in their function including lymphocyte mitogen responses and natural killer cell (NK) activity. The correlation of different measures of anxiety and depression and immune responses over time will further an understanding of the emotional response to childbearing in both mothers of VLBW and term infants and will identify key time periods when mothers are most likely to experience increased postpartal anxiety and depression. These data will be important in developing interventions and followup programs for mothers and their VLBW infants.